This reverts commit d7ece57e.

Reason for revert: failures on NumFuzz 
https://ci.chromium.org/p/v8/builders/ci/V8%20NumFuzz%20-%20debug/11818?

Original change's description:
> [turboprop] Add a slot for optimization marker in feedback vector
>
> Optimization marker and the optimized code used to share the same slot
> in the feedback vector as they were mutually exclusive. With turboprop
> we would want to mark the function for tier up to Turbofan while holding
> the optimized code for Turboprop. So this cl uses the existing padding
> field to hold the optimization marker instead.
>
> As a driveby, removes unused JSFunction::ClearOptimizedCodeSlot function
> and fixes a minor bug in Runtime_GetOptimizationStatus.
>
> Bug: v8:9684
> Change-Id: I18c551a69648a0837d16c5453d023c0b295b1521
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2467836
> Commit-Queue: Mythri Alle <mythria@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70789}

TBR=rmcilroy@chromium.org,mythria@chromium.org,jgruber@chromium.org

Change-Id: Ia9894fef713a522b9c3d349bef4abcde3e1e1832
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:9684
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2502870Reviewed-by: Mythri Alle <mythria@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70803}